The Scottish and Welsh governments have said they cannot recommend that legislative consent is given to the Brexit Repeal Bill as it stands.
In a joint statement, first ministers Nicola Sturgeon and Carwyn Jones described the European Union (Withdrawal) Bill as a “naked power-grab” that undermined the principles of devolution.
UK Scottish Secretary David Mundell countered that the legislation would result in a powers “bonanza” for Holyrood and said he was confident that legislative consent would be forthcoming.
Mr Mundell confirmed the approval of the Scottish Parliament through a legislative consent motion would be required for the Bill, which is designed to transpose EU law into British law so the same rules apply on the day of Brexit as the day before.
In their statement, Ms Sturgeon and Mr Jones said: “This week began with the Prime Minister calling for a constructive and collaborative approach from those outside Whitehall to help get Brexit right.
“Today’s publication of The European Union (Withdrawal) Bill is the first test as to whether the UK Government is serious about such an approach. It is a test it has failed utterly.
“We have repeatedly tried to engage with the UK Government on these matters and have put forward constructive proposals about how we can deliver an outcome which will protect the interests of all the nations in the UK, safeguard our economies and respect devolution.
“Regrettably, the Bill does not do this. Instead, it is a naked power-grab, an attack on the founding principles of devolution and could destabilise our economies.”
The statement continued: “The European Union (Withdrawal) Bill does not return powers from the EU to the devolved administrations, as promised.
“It returns them solely to the UK Government and Parliament, and imposes new restrictions on the Scottish Parliament and National Assembly for Wales.
“On that basis, the Scottish and Welsh governments cannot recommend that legislative consent is given to the Bill as it currently stands.”